Section 2.1 Earth's Crust in Motion

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Vocabulary

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Earthquake: the shaking and trembling that results from the movement of rock beneath Earth's surface

Stress: a force that changes the rocks shape and volume

Shearing: the stress where rocks slide past each other at opposite directions, sideways, releasing energy

Tension: the stress where rocks pull at different directions, causing the rock in the middle to stretch to its thinnest

Compression: the stress where rocks squeeze until the rock either bends or breaks

Deformation: any change of volume or shape of Earth's crust

Fault: a break in Earth's crust where slabs of stone slip past each other

Strike-Slip Fault: where two slabs of rock slip past each other in sideways or little up and down motion

Normal Fault: one half of the fault is on top while the other on the bottom

Hanging Wall: the half of the fault that lies above

Footwall: the half of the fault that lies below

Reverse Fault: same structure as a normal fault but the blocks move in opposite directions

Fault-Block Mountain: when normal faults uplifts a slab of rock

Folds: bends in rock that are formed by compression

Anticline: a fold in rock that bends upward into an arch

Syncline: a fold in rock that bends downwards into a bowl

Plateau: a large area of land that is elevated high above sea level

Outline

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Stress in the Crust

• triggers an earthquake
• stress

Types of Stress

• shearing
• tension
• compression
• deformation

Kinds of Faults

• strike-slip fault
• normal fault
  • hanging wall
  • footwall
• reverse fault

Friction along Faults

• friction

Mountain Building

• mountains formed by faulting
  • fault-block mountain
• mountains formed by folding
• anticlines
• synclines
• plateaus